Freeze



A ril 26, 1955 H. A. TOULMIN, JR 23,983

METHOD OF MANUFACTURING BUTTER Original Filed April 27, 1949 FREEZEDEHYDRATE TO 38% SOLIDS I i l THAW TO ROOM TEMPERATURE CHURN ANDCOALESCE BUTTER FAT EXTRACT SOLUTE EXTRUDE BUTTER CONTINUOUSLY INVENTORHARRY A. TOULM!N,JR. BY %v% ATTORNEYS United States Patent METHOD OFMANUFACTURING BUTTER Harry A. Toulmin, Jr., Dayton, Ohio, assignor toThe Commonwealth Engineering Company of Ohio, Dayton, Ohio, acorporation of Ohio riginal No. 2,505,654, dated April 25, 1950, SerialNo. 89,907, April 27, 1949. Application for reissue August 3, 1954,Serial No. 447,694

cation; matter printed in italics indicates the additions made byreissue.

This invention relates to the making of butter and, particularly, to amethod of making butter by a continuous process as distinguished fromthe customary batch type process according to the prior art.

Butter is made from both animal and vegetable products which containoils or fats. The animal product generally employed is milk, and,according to this invention, the milk can be converted directly intobutter, or the fats therein can first be concentrated and the buttermade therefrom. In connection with the making of butter from vegetableoils, a similar process is employed which may include a preliminaryconcentrating of the fats or oils therein, if found desirable.

Inasmuch as one of the most familiar butter products is table buttermade from cream, it is in connection with this product that thisinvention is particularly described. Itwill be understood, however, thatthe invention pertains to the making of all butters, whether fromvegetable or animal products.

it is well known that the formation of butter from cream is a process ofchanging a cream from a fat-dispersed-in-milk serum state to a state ofmilk serum-dispersed-in-fat. In general, this involves a mechanicalconversion of the butterfat from the small discrete globules suspendedin the serum to a coalesced condition wherein the fat globules aremerged into a substantially continuous mass which, upon the working outof a predetermined amount of the included serum, becomes commercialbutter.

From the foregoing it would appear that the only problem in connectionwith the making of butter from cream was the concentration of the fatuntil it coalesced into a continuous phase. This, however, is not true,because one of the most important characteristics of butter is itsflavor and odor, and both of these qualities are imparted to thefinished butter by substances at least partly entrained in the milkserum. Thus, the fat can be concentrated only to a certain degree whilestill retaining it in sufiicient serum to insure good flavor and odor inthe finished butter.

It'has also been found that when the butterfat is concentrated beyond acertain degree before making the butter, the resultant product will begreasy and oily in feel and appearance, and this, naturally, materiallydetracts from its commercial value.

In the art of manufacturing butter, then, not only must the fat globulesbe coalesced into a continuous phase, but, throughout the process ofeffecting this conversion, the factors which impart taste, odor andtexture to the final butter product must be carefully regulated. Theseseveral factors provide the considerations which have been largelydeterminative of the present practice of producing butter in batches,because, in this type of process, the adjustment of the qualitycontrolling factors and ratios is more easily accomplished. Themanufacture of butter by batch process is, however, relatively slow andexpensive. At best, different batches will produce butter of differentquality.

A preferable way of manufacturing butter, but one which has notheretofore been successfully accomplished, is that of producing butterby a continuous cycle and in a manner that takes into account theimportance of the above referred to critical quality controllingfactors.

The primary object of the present invention is the pro- Reissued Apr.26, 1955 vision of a method of making butter according to such acontinuous cycle.

Another object of this invention is the provision of a continuousbuttermaking process that maintains the proper flavor and odor in thefinished product.

Another object is to provide a continuous process for making butterwhich results in a product of highly uniform good quality.

According to my invention, the cream, which is preferably alreadyconcentrated to a certain degree by a centrifugal or gravitationalseparation thereof from the milk, is subjected to freezing, whereby themilk serum and fat separate to a certain extent, thus permitting thedraining off of at least part of the milk serum from the fat.Thereafter, the now concentrated fat is thawed to room temperature or toa somewhat lower temperature and is then churned or agitated to coalescethebutterfat into a continuous phase. At this time the cream changesfrom a solution of fat in serum to one of serum in fat, with a largepart of the serum existing as free liquid.

The free liquid is readily drained oil, and the fat, now semisolid andcontinuous in phase, may be extruded as butter. The extrusion of thebutter is preferably accompanied by pressure or some mixing or kneadingthereof so the butter is worked" and gives up some of the serumentrained therein. By adjusting the amount of working of the butterduring the extrusion thereof the amountof serum remaining therein togive the final butter product the proper texture and consistency can beregulated. Also, should it be desirable to add salt or coloring matter,it is preferably accomplished at this time so that it be comesthoroughly admixed with the butter being extruded. The extruded butter,being a completed and uniform product, may now be packaged formarketing.

The accompanying drawing illustrates somewhat more in detail the processaccording to this invention, although it will be understood that thepractice of this invention is not limited to the precise proportions,ratios, temperatures, and the like set forth in the process illustratedin the drawing.

Referring to the drawing, it will be seen that the first step inconnection with manufacturing butter according to my process is thefreezing of the cream and a dehydration thereof to about 38 per centsolids.

In connection with the freezing and dehydration step, it will beunderstood that there are a number of different ways in which this canbe carried out. For example, the cream could be'subjected to pressure,as by a hydraulic or mechanically driven ram, after being frozen, andthereby squeeze out a certain amount of the milk serum therefrom.Another manner of effecting the se aration of the cream and milk serumwould be to centri ge the frozen product until the desired degree ofseparation of fat and milk serum took place. In any case, the butter fatis concentrated to approximately the best degree for rapid churningwhile still retaining a sufficient milk serum to impart the necessarycharacteristics to the butter required by commercial practice.

The second step in the process is the thawing of the frozen anddehydrated cream to a temperature which will permit churning thereof. Asshown in the chart, the dehydrated cream may be thawed to roomtemperatures, but in certain instances, it may be preferable to hold thecream at a temperature lower than this. The churning characteristics ofthe cream will be largely determinative of this, as well as the economyit is necessary to observe in connection with the degree of conversionof the fat to butter.

After the dehydrated cream has been thawed to the desired churningtemperature, it is then churned or agitated in some manner in order tocoalesce the butter fat into a continuous phase. This churning may beaccomplished by mechanical agitators or beaters, or by blowing gasthrough the cream, or by otherwise agitating the cream so that theglobules of butterfat are brought into intimate contact with each otherwith sufficient force to cause them to coalesce.

The conversion of the butterfat into a continuous phase is accomplishedby a release of a substantial amount of the milk serum or solute as afree liquid. This free sense liquid, is, of course, readily extractedfrom the mixture by a simple process of draining it off gravitationally.The product remaining after the free liquid is poured is the coalescedbutterfat, having milk serum entrained therein ll} tfhe form of finedroplets dispersed throughout the mass at.

In order to-bring this mixture into the proper condition, it isdesirable to knead or work the mass to remove a portion of the entrainedserum therefrom. This is preferably accomplished simultaneously with theex trusion of the butter by carrying out the extrusion with a suitablyformed screw type extruding mechanism or the like which will at one timeapply pressure to the butter while also kneading or working it.

Should the product desired be sweet butter, then no salt is added,although there may be just prior to the extruding of the butter acertain amount of coloring matter added in order to give the product theproper color. However, if the usual type of salted butter is desired,then the salt and coloring matter, if desired, is added to the butterjust prior to its extrusion, so that it is thoroughly worked into andadmixed with the butter.

It will be evident that the foregoing process, with the possibleexception of the initial dehydration step, can be carried out as acontinuous cycle, and that in this manner, the production is relativelyuniform, and a minimum of equipment is required.

It will also be understood that the cream, either prior or subsequent tothe dehydrating step, is preferably ripened, either by natural aging orby the addition thereto of a suitable ripening agent. It will beunderstood, however, that the particular manner of ripening the cream toproduce the proper flavor and odor in the finished product is notnecessarily a part of this invention, but is a step well known andpracticed in the art of butter manufacture.

The process described above is in connection with the manufacture oftable butter from cream, but, as mentioned before, this invention is notintended to be limited to the manufacture of that particular type ofbutter but is intended to include within its scope the manufacture ofall butters which are arrived at by the concentration and subsequentcoalescing of fat or oil particles in either animal or vegetableproducts.

An essential step in connection with the making of butter from any oilor fat bearing substance according to this invention is that of freezingand dehydrating the substance, whereby the said fat or oil thereinbecomes concentrated.

It will be understood that I do not wish to be limited to the exactproportions, ratios, and other factors specifically set forth in theforegoing description and the accompanying drawing but desire tocomprehend such changes thereof as may be further desirable to adapt myinvention to dilferent conditions and usages.

I claim:

1. The method of making butter which comprises: freezing an oil bearingsubstance and removing water therefrom while frozen to concentrate theoil therein, thawing the concentrated substance and churning the thawedsubstance to coalesce the oil therein to make butter.

2. The method of making butter which comprises: freezing a fat bearingsubstance and extracting water therefrom while so frozen to concentratethe fat, thawing the concentrated substance, and agitating the thawedsubstance to coalesce the fat therein to convert the said fat to a stateof continuous phase.

3. The method of making butter which comprises. freezing cream and atleast partially dehydrating the cream by removing milk serum therefromwhile frozen, thawing the concentrated cream, churning the thawed creamto coalesce the fat therein, and draining the free milk serum from themixture of coalesced butterfat and serum.

4. The method of making butter which comprises: freezing cream and atleast cream by removing milk serum therefrom while frozen, thawing theconcentrated cream, churning the thawed cream to coalesce the fattherein, draining the free milk serum from the mixture of coalescedbutterfat and serum, and working the coalesced butterfat to extract aportion of the entrained serum therefrom.

5. The method of making butter which comprises: freezing cream and atleast partially dehydrating the partially dehydrating the cream byremoving milk serum therefrom while frozen, thawing the concentratedcream, churning the thawed cream 'to coalesce the fat therein, drainingthe free milk serum from the mixture of coalesced butterfat and serum,working the coalesced butterfat to extract a portion of the entrainedserum therefrom, and extruding the worked butter.

6. The method of making butter which comprises: freezing cream andremoving at least a portion of the milk serum therefrom while frozen,thawing the concentrated cream, churning the thawed cream to coalescethe fat therein, draining milk serum from the churned cream leaving thecoalesced butterfat, working the coalesced butterfat to extract a partof the entrained serum therefrom, adding salt to thebutter while it isbeing worked, and extruding the worked and salted butter.

7. The method of making butter which comprises: freezing cream andremoving at least a portion of the milk serum therefrom while frozen,thawing the concentrated cream, churning the thawed cream to coalescethe fat therein, draining milk serum from the churned cream leaving thecoalesced butter fat, working the coalesced butterfat to extract a partof the entrained serum therefrom, adding salt and coloring matter to thegutter while it is being worked, and extruding the worked utter.

8. The method of making butter continuously which comprises: freezing amixture of milk serum and butterfat and extracting milk serum therefromwhile frozen, thawing the concentrated cream, agitating the thawed creamto coalesce the butterfat therein, extracting the free milk serumreleased by the coalescing of the butterfat, kneading the coalescedbutterfat, extruding the kneaded butterfat, and carrying out theforegoing steps as a continuous cycle.

9. The method of making butter continuously which comprises: freezing asuspension of butterfat in milk serum and extracting serum therefromwhile frozen to reduce the mixture to approximately 38 per cent solids,thawing the frozen mixture to approximately room temperature, andthereafter agitating the mixture to coalesce the butterfat therein,kneading the coalesced butterfat while simultaneously extruding thesame, and extracting serum during the aforementioned agitating, kneadingand extruding.

10. In the art of manufacturing butter, the method of preparing creamfor churning which comprises: freezing the cream, and extracting milkserum from the frozen cream thereby to increase the concentration of thebutterfat in the cream.

11. In the art of manufacturing butter, the methodof preparing cream forchurning which comprises: freezing the cream, and extracting milkserumfrom the frozen cream to raise the concentration of the butterfattherein to the order of 38 per cent.

12. The method of making butter from an aqueous mixture having fatparticles in suspension therein which comprises: freezing the mixtureand removing at least a part of the water therefrom while in the frozenstate, thawing the mixture, agitating the thawed mixture to coalesce thefat therein, draining further'water from the churned mixture leaving thecoalesced fat, and kneading the coalesced fat until it is uniformthroughout.

13. A method of making butter from an aqueous mixlure containing fatparticles which comprises the steps of (a) subjecting said aqueousmixture to refrigeration to cause a substantial amount of the waterpresent to form ice crystals, (b) separating at least a part of said icecrystals from the mixture as formed during refrigeration, (c) thawingthe resultant mixture to melt the ice crystals therein, (d) agitatingthe thawed mixture, and (e) separating the water from the agitatedmixture leaving coalesced fat.

References Cited in the file of this patent or the original patentUNITED STATES PATENTS 913,920 Schou Mar. 2, 1909 1,791,069 Wendt Feb. 3,1931 2,150,943 Sharples Mar. 21, 1939

